Methods and apparatus for medical device cursor control and touchpad-based navigation

ABSTRACT

The invention provides, in some aspects, medical apparatus with software-based cursor control and graphical user interface hotspot selection. This can be used, by way of non-limiting example, as part of a graphical user interface by which doctors, nurses, patient care technicians, other health care providers, and/or patients can enter data into enter data and/or to control the apparatus and/or associated medical equipment.

This application is a divisional of U.S. patent application Ser. No.12/355,082, filed Jan. 16, 2009, entitled “METHODS AND APPARATUS FORMEDICAL DEVICE CURSOR CONTROL AND TOUCHPAD-BASED NAVIGATION,” theteachings of the aforementioned application is incorporated herein byreference

BACKGROUND OF THE INVENTION

The invention pertains to medical treatment apparatus and methods and,more particularly, to user interfaces therefor. The invention hasapplication in facilitating user interaction with medical apparatus,such as peritoneal dialysis equipment, by way of non-limiting example.

Today, computers can be found nearly everywhere, including in medicalequipment at hospitals, laboratories, and even patients' bedsides. Theequipment typically includes, in addition to a central processing unitand monitor, a keyboard, mouse and/or other input devices. The latterallow users (e.g., doctors, nurses, patient care technicians, otherhealth care providers, and/or patients themselves) to enter data and/orto control the medical equipment—often, by selecting from among optionsdisplayed on the monitor. Mice and keyboards, in particular, have fallenout of favor in healthcare settings due to recent studies implicatingthem in the spread of disease. They are increasingly being replaced withtouchpads and touch screens, which can be cleaned more easily.

There are a number of challenges in designing computerized medicalequipment, not the least of which is integrating keyboards, mice,touchpads, or other input devices with displays (on the monitor) to form“user interfaces” that can be readily understood and efficientlyoperated. A good user interface, for example, must respond to user input(e.g., keyboard taps or mouse motions) quickly and accurately. Often apointer or cursor, that is, a graphic shaped like an arrowhead, plussign, pointing finger, an “I” bar, or the like identifying the target ofuser input, is instrumental in providing that feedback. Yet this raisesa further challenge: integrating keyboards, mice, touchpads (or otherinput devices), and displays with the cursor. Various solutionsaddressing these issues (for example, hardware-based cursor controlcircuitry) have been suggested in the prior art, but these can be costlyand/or limiting.

An object of the invention is to provide improved medical treatmentapparatus and methods. Related objects provide such apparatus andmethods as can be used in a wide variety of medical settings, fromlaboratory to bedside.

A further object of the invention is to provide such apparatus andmethods as facilitate integration of computers with medical equipment. Astill further object of the invention is to provide such apparatus andmethods as facilitate integration of input devices with such computersand/or medical equipment.

A still further object of the invention is to provide such apparatus andmethods as facilitate display of a user interface.

Yet a still further object of the invention is to provide such apparatusand methods as can be readily implemented and used on a range ofavailable platforms.

SUMMARY OF THE INVENTION

The foregoing objects are among those attained by the invention whichprovides, in some aspects, medical apparatus with software-based cursorcontrol. This can be used, by way of non-limiting example, as part of agraphical user interface by which doctors, nurses, patient caretechnicians, other health care providers, and/or patients enter datainto and/or control the apparatus and/or associated medical equipment.

Medical apparatus according to one such aspect of the invention includesa user interface system with a main image subsystem, a cursor subsystem,a monitor, graphics logic, and a video memory. The main image subsystemstores, e.g., to the video memory, data structures and/or otherinformation (collectively, “screen-representative information”)representing graphics and/or text to be displayed on the monitor. Thecursor subsystem modifies at least a portion of thescreen-representative information in the video memory, replacing it withdata structures and/or other information (collectively,“cursor-representative information”) representing a cursor graphic(e.g., an icon representing an arrowhead) to be displayed on themonitor. The graphics logic drives screen- and/or cursor-representativeinformation from the video memory to the monitor for display of thegraphics and/or text represented thereby. The cursor subsystem respondsto a change in cursor-representative information previously written byit to the video memory by re-writing that information to the videomemory.

Related aspects of the invention provide medical apparatus as describedabove in which, in connection with storing screen-representativeinformation to the video memory, the main image subsystem changes (e.g.,overwrites) cursor-representative information previously written by thecursor subsystem to that memory.

Further related aspects of the invention provide medical apparatus asdescribed above in which (i) the cursor-representative informationcomprises bit patterns representing the cursor to be displayed on themonitor, and (ii) the cursor subsystem writes those bit patterns to thevideo memory at a location corresponding to that at which the cursor isto be displayed on the monitor.

Still further related aspects of the invention provide medical apparatusas described above in which (i) the screen-representative informationcomprises bit patterns representing the graphics and/or text to bedisplayed on the monitor, and (ii) the main image subsystem writes thosebit patterns to the video memory at one or more locations correspondingto those at which such graphics and/or text are to be displayed.

Yet still further related aspects of the invention provide medicalapparatus as described above in which the cursor subsystem detects achange in a bit pattern previously written by it to the video memory andresponds to such by re-writing that bit pattern.

In a related aspect of the invention, the cursor-representative bitpatterns written to the video memory by the cursor subsystem of medicalapparatus as described above are distinguishable from the graphics-and/or text-representative bit patterns written to that memory by themain image subsystem. For example, the bit patterns written by thecursor subsystem can comprise one or more colors, numerical rangesand/or sequences not typical to or represented by the bit patternswritten by the main image subsystem.

In a further related aspect of the invention, the cursor subsystem ofmedical apparatus as described above can test the values in the videomemory in order to detect a change in a bit pattern previously writtenby it to the video memory. Such testing can be for, by way of example,colors, numerical ranges and/or sequences of the type written by thecursor subsystem (but not typically by the main image subsystem) to thevideo memory.

Further aspects of the invention provide medical apparatus as describedabove in which, in connection with modifying at least a portion of thescreen-representative information in the video memory, the cursorsubsystem stores to a buffer a portion of the screen-representativeinformation that it replaces with cursor-representative information. Forexample, in aspects of the invention, wherein the screen- andcursor-representative information comprise bit patterns, the cursorsubsystem can, for example, (i) write cursor-representative bit patternsto the video memory at a location corresponding to that at which acursor us to be displayed on the monitor, and (ii) write graphics-and/or text-representative bit patterns previously in that location ofthe video memory to the buffer.

In other aspects, the invention provides medical apparatus, e.g., of thetype described above, that additionally includes a touchpad and touchpadsubsystem. According to these aspects, the main image subsystem storesto the video memory screen-representative information for a userinterface that includes text and/or graphics representing buttons,widgets (e.g., dialog boxes, dials, numeric digit wheels, alphacharacter wheels, check boxes, etc.) and/or other items (e.g., menus)for display at locations selectable and/or manipulable by a user (i.e.,“hot spots”). The touchpad subsystem identifies gestures on the touchpadand generates notifications in response to them. Those gestures includeat least a contacting touch of length (e.g., a linear or curvilinearswipe) and may additionally include a tap or point touch (i.e., acontacting touch of substantially no length). The notifications canindicate the gesture type, location, magnitude and/or direction.

In further accord with these aspects of the invention, an application(or other functionality, e.g., middleware/software) that defines theuser interface responds to those notifications by highlighting (oractivating) a hot spot. That application (or other functionality) can,instead or in addition, treat the notifications as indicative ofsubstantive user input, e.g., numeric, alpha or other value selectionsbased on the type of activated hot spot, the user-selectable valuesassociated with it, the gesture type, location, magnitude and/ordirection. According to related aspects of the invention, the cursorsubsystem can be coupled to the application and can receive from itlocations of hot spots onto which a cursor is to be overlaid for displayon the monitor.

By way of example, in medical apparatus according to these aspects ofthe invention, the touchpad subsystem can respond to a user's upwardswipe of the touchpad by sending a corresponding notification toapplication software that defines a user interface currently displayedon the monitor. The application (or other functionality) can, in turn,determine that a new hot spot should be activated—e.g., one just above acurrently activated hot spot. The application can generate acorresponding application window, with that new hot spot highlighted,for rendering on the monitor by the main image subsystem and graphicslogic. By way of further example, the application can respond tosubsequent notification, from the touchpad subsystem, of a user'sdownward swipe on the touchpad by selecting a first user-selectable itemin the currently selected hot spot—both generating a new applicationwindow with that item selected and taking a value associated with thatitem as an input. By way of further example, in the case of an activatedwidget that displays an alpha character, a digit or other enumeratedvalue (e.g., a word from a dictionary, a value from a list ofpermissible values, and so forth), the application can respond to aswipe on the touchpad by incrementing or decrementing that displayedvalue (depending on the direction of the swipe) and accepting thefinally selected value (as indicated, e.g., by a confirmatory tap or acessation of motion) as an input.

Yet still further aspects of the invention provide medical apparatus asdescribed above in which the cursor subsystem can effect display of acursor graphic at cursor display position newly determined as a functionof a current cursor display position and a gesture type, location,magnitude and direction. Systems according to this aspect of theinvention can effect display of such a graphic, e.g., by modifying videomemory in the manner discussed above.

Further aspects of the invention provide systems employing combinationsof the features described above.

Yet still further aspects of the invention provide methods for operationof medical apparatus with a (graphical) user interface paralleling theoperations described above.

These and other aspects of the invention are evident in the drawings andin the description that follows.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the invention may be attained byreference to the drawings, in which:

FIG. 1 depicts a patient treatment system according to one practice ofthe invention;

FIG. 2 depicts functional elements of a system of the type shown in FIG.1;

FIG. 3 is a data-flow diagram illustrating the flow of data and controlsignals in a system of the type shown in FIG. 1 for purposes of cursordisplay;

FIG. 4 is a flowchart illustrating a method of cursor repositioning andrefreshing in a system of the type shown in FIG. 1;

FIGS. 5a, 5b, 5c, 5d, 5e, 5f, 6a, 6b, 6c, 6d, 6e , 6 f, 7 a, 7 b, 7 c, 7d, 7 e, 8 a, 8 b, 8 b, and 8 c illustrate hotspot selection via atouchpad in a system of the type shown in FIG. 1; and

FIG. 9 is a data-flow diagram illustrating a flow of data and controlsignals in a system of the type shown in FIG. 1 for purposes of hotspotselection.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT

FIG. 1 depicts a medical apparatus according to one practice of theinvention, as well as an environment of the type in which the inventioncan be practiced. The apparatus 10 shown in that figure and describedbelow, by way of non-limiting example, is a data entry station, thoughit will be appreciated that in other embodiments apparatus 10 maycomprise any of a variety of other apparatus for controlling, collectingdata from and/or interfacing with medical equipment.

Illustrated data entry station 10 is used in connection with medicaltreatment apparatus 12 (here, dialysis equipment) to facilitatetreatment of patients 14 and, more particularly, to facilitate dataentry by doctors, nurses, patient care technicians, other health careproviders, and/or patients, collection of data from apparatus 12, and/ormonitoring and control of that apparatus 12. The device 10 comprises adigital data processor 20, a monitor 16, and a touchpad 18 or otherinput device (e.g., keyboard, mouse and/or touchscreen). Although twoapparatus 12 are shown, those skilled in the art will appreciate thatthe data entry station 10 may support fewer or more than two suchapparatus and, indeed, may be used without such apparatus 12—or may beincorporated directly into it.

In the illustrated embodiment, monitor 16 displays information relatingto medical treatment apparatus 12, treatment of patient 14 and/or otheraspects of patient care, all under the control of a digital dataprocessor 20. This includes, by way of non-limiting example, graphicsand/or text generated by software applications executing on the digitaldata processor 20 (e.g., in connection with data or other informationgenerated by apparatus 12), as well as graphics and/or text defining a“user interface” generated by such software applications or otherwise.That user interface is used by a doctor, nurse, patient care technician,other health care provider, patient or other user to interact with thestation 10 and/or apparatus 12 for purposes, by way of non-limitingexample, of reviewing patient care information, entering data, issuingcommands, and so forth. As used in this paragraph and throughout,“graphics” refers to images and other visual display elements.

Monitor 16 of the illustrated embodiment comprises a liquid crystaldisplay, cathode ray display, plasma display, light emitting diodedisplay, or other display of the type commercially available in themarketplace, albeit operated in accord with the teachings hereof. Inother embodiments, information displayed on monitor 16 can be output,instead or in addition, to a monitor provided with apparatus 12, to aprinter (not shown) or other output device (local or remote) via awired, wireless, networked communications link.

Illustrated touchpad 18 generates signals indicative of a user's touch.The touchpad 18 comprises a conventional such device of the typegenerally available in the marketplace, albeit operated in accord withthe teachings hereof. In other embodiments, touchpad 18 can besupplemented with or supplanted by other input devices, such as atouchscreen or mouse, for user input. For sake of convenience, theteachings that follow assume that user input is provided (at least inpart) via touchpad 18; however, it will be appreciated that suchteachings are equally applicable to input via touchscreen, mouse, and soforth.

Illustrated digital data processor 20 controls the data entry station10, e.g., interfacing with treatment apparatus 12, collecting and/oranalyzing patient data, generating information including theaforementioned user interface for display on the monitor 16, acceptinginput from the user (including via touchpad 18), storing and/ortransmitting data (and/or other information) to databases and/or remotesystems, and so forth. The digital data processor 20 of the illustratedembodiment comprises a workstation or personal computer of the typegenerally available in the marketplace, albeit as adapted in accord withthe teachings hereof. In other embodiments, it may comprise an embeddedprocessor, workstation, minicomputer, mainframe, or other digital dataprocessing device of the type known in the art, again, as adapted inaccord with the teachings hereof.

The digital data processor 20 may be a stand alone device as shown inthe drawing, or may be integral to one or more other components of theillustrated system, e.g., the monitor 16 and/or medical treatmentapparatus 12. It may, moreover, be coupled for communication with themonitor 16 and touchpad 18 via wireless connection (e.g., BlueTooth,802.1x, or otherwise), wired connection (e.g., Ethernet or backplanebus) or otherwise, all in the conventional manner known in the art.

FIG. 2 illustrates the make-up of digital data processor 20 according toone practice of the invention. Illustrated device 20 generally compriseshardware 22, operating system 24, middleware/software 26, andapplications 28, configured and operated in the conventional mannerknown in the art as adapted in accord with the teachings hereof.

Hardware 22 of the illustrated embodiment comprises central processingunit (CPU) 22 a, random access memory 22 b, port 22 d (to which touchpad18 or other input device(s) is/are coupled), video memory 22 e, and agraphics logic 22 f (to which monitor 16 or other output device(s)is/are coupled). These comprise conventional components of such typeknown in the art for use in digital data processor 20, configured andoperated in the conventional manner known in the art, albeit, as adaptedin accord with the teachings hereof. Thus, by way of non-limitingexample, graphics logic 22 f comprises a graphics card, graphics chipset, graphics processing unit and/or other functionality of the typeknown in the art (as adapted in accord with the teachings hereof)capable of driving bit patterns or other representations generated byapplications 28, middleware/software 26 and/or operating system 24 a tomonitor 16 for display thereon. Illustrated hardware 22 additionallyincludes buffer 22 c (which is occasionally referred to herein as a“behind-the-cursor array,” in reference to the software structure thatmaps onto buffer 22 c) which may be implemented in RAM 22 b, VRAM 22 e,or other memory.

The components of hardware section 22 illustrated in FIG. 2 are by wayof example only; other embodiments may incorporate other components,instead or in addition. Moreover, in other embodiments, one or morefunctions performed by the hardware components may be performed insoftware, firmware and/or vice versa.

Operating system 24 manages and coordinates execution of software andhardware 22 of a digital data processor 20, in the conventional mannerknown in the art (as adapted in accord with the teachings hereof). Theoperating system 24 comprises Unix, Microsoft Windows, Mac OS X, Linux,Solaris, or other operating system software of the type known in theart, as adapted in accord with the teachings hereof. In alternateembodiments, functionality of the operating system 24 may be embodied inone or more other hardware and/or software components.

In the illustrated embodiment, operating system 24 includes, inter alia,main image subsystem 24 a, which is responsible for effecting storage,e.g., to video memory 22 e, of data structures and/or other information(collectively, “screen-representative information”) representing thescreens generated by applications 28, middleware/software 26 and/or(other) operating system utilities to video memory 22 e, whence graphicslogic 22 f drives it to monitor 16 (or other output device) for display.

The data structures and/or other information that make up thescreen-representative information includes, as is conventional in theart, codes or bit patterns (collectively, “bit patterns”) that governthe display characteristics of the text and graphics—or portions thereof(e.g., pixels)—that make up the application windows as displayed onmonitor 16. Those characteristics include, again, as is conventional inthe art, color, intensity, and so forth. In the illustrated embodiment,bit patterns included in screen-representative information can, forexample, cover the conventional gamut of colors generated byapplications programs 28, e.g., 32-bit color, 16-bit color, 8-bit color,and so forth.

Main image subsystem 24 a of the illustrated embodiment comprisesconventional software—such as a “windowing” subsystem—of the type knownin the art (as adapted in accord with the teachings hereof) forproviding windowing functionality. Though shown, here, as part ofoperating system 24, in other embodiments, main image subsystem 24 a maycomprise components within the middleware/software 26, applications 28and/or hardware 22.

In the illustrated embodiment, middleware/software 26 comprise softwaremodules that facilitate execution and implementation of functionsrequested and/or performed by applications 28 (as well, potentially, byoperating system 24). This can include, by way of non-limiting example,graphics, mathematical/statistical and other runtime libraries of thetype commercially available in the marketplace. In the illustratedembodiment, this includes a touchpad subsystem 26 b and a cursorsubsystem 26 a, as further discussed below and elsewhere herein. Inalternative embodiments, the functions implemented bymiddleware/software 26 can be implemented directly in applications 28,operating system 24, as web services on remote digital data processingsystems to which digital data processor 20 is coupled, and/or inhardware 22.

Applications 28, including exemplary application 28 a, compriseconventional software of the type known in the art for use in healthcare environments, including, by way of non-limiting example, softwarefor interfacing with treatment apparatus 12, collecting and/or analyzingpatient data, generating information (including the aforementioned userinterface), accepting input from the user, storing and/or transmittingdata (and/or other information) to databases and/or remote computersystems, and so forth—e.g., with the assistance of themiddleware/software 26, operating system 24 and hardware 22.

To this end, the application 28 a (by way of example), generates windows(“application windows”) or screens in the conventional manner known inthe art (as adapted in accord with the teachings hereof) withinformation—e.g., text and graphics—to be displayed on monitor 16. Thesescreens can include information pertaining to apparatus 12, the patient,his/her condition and/or treatment, and so forth. They can, in additionor instead, include buttons, widgets (e.g., dialog boxes, dials, numericdigit wheels, alpha character wheels, check boxes) and/or other items(e.g., menus) for display at locations selectable and/or manipulable bya user (i.e., “hot spots”) in the conventional manner of a userinterface and, more particularly (by way of non-limiting example), agraphical user interface (“GUI”), again, as adapted in accord with theteachings hereof. As noted above, the main image subsystem 24 a storesscreen-representative information representing the screens generated byapplication 28 a to VRAM 22 e, whence the graphics logic 22 f drives itto monitor 16.

Cursor Subsystem

The cursor subsystem 26 a comprises software that effects display of acursor—e.g., a visual element shaped like an arrowhead, plus sign,pointing finger, an “I” bar, or the like—on the monitor. Unlikeprior-art hardware-based systems, the cursor subsystem 26 aadvantageously does this by “writing over,” yet, retaining,screen-representative information (representing text and/or graphicsgenerated by application 28) in the video memory—and, more particularly,by (i) replacing screen-representative information in that memory 22 ewith data structures and/or other information (collectively,“cursor-representative information”) representing a cursor graphic to bedisplayed on the monitor, and (ii) caching the replacedscreen-representative information so that it can be restored if/when thecursor is subsequently repositioned.

As with the screen-representative information, the data structuresand/or other information that make up the cursor-representativeinformation include bit patterns that govern the display characteristicsof the cursor as displayed on monitor 16. Those characteristics include,again, as is conventional in the art color, intensity, and so forth. Insome embodiments, by way of non-limiting example, bit patterns includedin cursor-representative information represent colors falling outsidethe gamut of colors generated by applications programs 28, e.g., outsidethe conventional 32-bit color, 16-bit color, and 8-bit color gamuts, andso forth. Alternatively, in some embodiments, bit patterns included incursor-representative information represent colors fall within thegeneral color gamut utilized by the applications program 28, butrepresent, unique colors or color combinations within that gamut. Moregenerally, the cursor subsystem 26 a generates and stores to memory 22 ecursor-representative signals including bit patterns indicative ofcolor(s), numerical ranges and/or sequences not typical to orrepresented by the bit patterns written by the main image subsystem onbehalf of the applications program 28 a.

Cursor Positioning and Repositioning

In the illustrated embodiment, the subsystem 26 a modifies memory 22 edirectly and/or using componentry (of the operating system 24 and/ormiddleware/software 26) other than the main image subsystem 24 a.However, in other embodiments, subsystem 26 a employs subsystem 24 a,instead or in addition, to so modify memory 22 e. As above, graphicslogic 22 f drives the contents of the video memory 22 e, here, includingboth the screen-representative information and the cursor-representativeinformation, to the monitor 16 in order to effect a display thatincludes a cursor in addition to the screens generated by theapplication 28 a.

Subsystem 26 a does not replace all screen-representative information inthe memory 22 e with cursor-representative information but, rather, onlythat disposed at a location (in video memory 22 e) corresponding to thatat which the cursor is to be displayed on the monitor. At initiation,e.g., boot-up of application 28 a, subsystem 26 a effects display of thecursor at a default location, e.g., the center or corner of amost-recently generated application window. Typically, the subsystem 26a effects repositioning of the cursor in response to user touch/movementof the touchpad 18, as detailed more fully below; although, it can alsoeffect a reset of the cursor position in absence of such touch/movement,e.g., following the close of an application window, activation of GUIwidgets (or hotspots), and so forth.

Regardless, the subsystem 26 a “caches” the screen-representativeinformation (representing text or graphics generated by the main imagesubsystem 26 b) before replacing it in memory 22 e withcursor-representative information. It does this by storing thescreen-representative to the behind-the-cursor array (or butter) 22C.That array (which as noted above, can map to storage forming part of RAM22 b, VRAM 22 e, or other memory) is sized sufficiently to hold thatinformation—optionally, by way of non-limiting example, along withcurrent and/or prior cursor positions, which can be stored relative tothe VRAM 22 e indexing scheme or the corresponding reference frame(e.g., coordinate system) of the monitor 16.

By caching the screen-representative information, the subsystem 26 a canrestore that information in VRAM 22 e when the cursor is repositioned,e.g., in response to user touch/movement of the touchpad 18, followingthe close of an application window, activation of GUI widgets (orhotspots), and so forth. This has the practical effect of restoring onmonitor 16 text or graphics that had been generated by the application28 a (and written to VRAM 22 e by the main image subsystem 24 a) andthat “written over” by the cursor subsystem 26 a.

FIG. 3 is a data-flow diagram depicting, by way of non-limiting example,a manner in which the cursor subsystem 26 a is notified of suchrepositioning and the actions effected by it in response. Particularly,as shown in that drawing, a user of data entry station 10 effectsmovement of the cursor displayed on monitor 16 by touching and/or movinghis/her finger on the touchpad 18 (or other device) in the conventionalmanner known in the art, as adapted in accord with the teachings hereof.This can be in connection with setting or altering a target of input,pointing to region of interest, or otherwise. The touchpad 18 respondsby generating signals indicative of that touch/movement for input toserial port 22 d, which in turn generates an interrupt for applicationto CPU 22 a along with the touch/movement information—all in theconventional manner known in the art. Operating system 24 notifiescursor subsystem 26 a of the touchpad activity and makes thattouch/movement information available to it. This can be effected, by wayof non-limiting example, by interrupt handling-code that comprisesand/or invokes the cursor subsystem 26 a and that stores thetouch/movement information to memory for use by it. Though not shown inFIG. 3, it will be appreciated that cursor subsystem 26 a can benotified of cursor repositioning in other ways and/or via differentmechanisms (e.g., following the close of an application window, displayof GUI widgets, and so forth).

Upon notification of cursor repositioning, cursor subsystem 26 a assumesor calculates a new cursor display position based on the touch/movementinformation supplied to it by the operating system 24 and/or the priorcursor position (as stored, for example, in array/buffer 22 c).Calculation, where necessary, can include by way of non-limiting examplemapping touchpad coordinates to the VRAM 22 e indexing scheme and/orcorresponding reference frame (e.g., coordinate system) of the monitor16. Where the user's motion is a “swipe” or other gesture, suchcalculation can also include by way of further non-limiting example,extrapolating a desired new cursor position from a prior cursor positionand a position/magnitude/direction of the gesture—though, in theillustrated embodiment, the cursor subsystem relies on application 28 ato define new cursor position following a swipe or other such gesture,as described below. In the illustrated embodiment, the cursor subsystem26 a stores the newly determined cursor position to array/buffer 22 c,as noted in FIG. 3.

As evident in the discussion above, upon determination of a new cursorposition, the cursor subsystem 26 a restores to VRAM 22 escreen-representative information cached to array/buffer 22 c for theprior cursor position. This, as noted, has the practical effect ofrestoring on monitor 16 text or graphics that had previously been“written over” by the cursor subsystem. At the same time, the cursorsubsystem effects display of the cursor at the new cursor location viathe methodology described above, e.g., by replacingscreen-representative information in VRAM 22 e at locationscorresponding to the new cursor position with cursor-representativeinformation and caching that screen-representative position toarray/buffer 22 c.

Cursor Refreshing

Main image subsystem 24 a and cursor subsystem 26 a of the illustratedembodiment operate independently, or relatively so, vis-a-vismodification of VRAM 22 e and, thereby, displays on monitor 16. Thus, asdiscussed in the prior section, subsystem 26 a overwrites, yet, retains,screen-representative information from subsystem 24 a withcursor-representative information in order to effect display of a cursorat user- or application-designated position).

As a further consequence of this (relative) independence, subsystem 24 acan overwrite cursor-representative information from subsystem 26 a withscreen-representative information, e.g., in response to applicationwindows or screens generated by application 28 a in the normal of itsoperation. However, unlike the cursor subsystem 26 a, main imagesubsystem 24 a of the illustrated embodiment need not retain thecursor-representative information it overwrites. This facilitates use ofconventional applications software 28 in device 10 and, moreparticularly, on digital data processor 20.

To prevent this action of the main image subsystem 24 a from eliminatinga stationary cursor from displaying on monitor 16, cursor subsystem 26 aperiodically tests VRAM 22 e to determine whether cursor-representativeinformation still exists at the expected and current cursor location inVRAM. If not, the subsystem 26 a re-effects display of the cursor thatlocation via the methodology described above, e.g., by replacingscreen-representative information in VRAM 22 e at that location withcursor-representative information. The subsystem 26 a can simultaneouslycache that screen-representative position to array/buffer 22 c; though,unless the main image subsystem 24 a has since written newscreen-representative information to that location in VRAM 22 e, this isnot necessary.

In the illustrated embodiment, cursor subsystem 26 a preferably testsVRAM 22 e for the presence of expected cursor-representative informationat intervals sufficiently short that overwriting of that information bymain image subsystem 24 a will not be detected by—or, at least, not becognitively perceived by and, at very least, not result in irritationof—users viewing monitor 16. The this end, cursor subsystem 26 apreferably tests VRAM 22 e and (if necessary) rewritescursor-representative information to it at the expected cursor locationin intervals of under ¼ sec. and, more preferably, under 1/10 sec. and,still more preferably, under 1/60 sec.

To perform this testing, cursor subsystem 26 a of the illustratedembodiment relies on differences in the codes or bit patterns(collectively, “bit patterns”) that make up cursor-representativeinformation and screen-representative information, respectively. Thus,by way of non-limiting example, in embodiments wherescreen-representative information written by the main image subsystem 24a to memory 22 e include bit patterns indicative of colors within an8-bit color gamut and where cursor-representative information written bythe cursor subsystem 26 a to that memory include non-overlappingcolor(s) within a 16-bit gamut, the subsystem 26 a can test for thosenon-overlapping color(s) to determine the presence or absence ofexpected cursor-representative information. This is likewise true where,by way of non-limiting example, the bit patterns written by the cursorsubsystem 26 s (a) fall within the same color gamut as those written bythe main image subsystem 24 a, but (b) utilize colors not used by themain image subsystem 24 a.

A further understanding of the operation of the cursor subsystem may beattained by reference to FIG. 4, which is a flowchart illustrating theoperations discussed here and in the prior section in regard to cursorrepositioning and refreshing. A still further understanding of theoperation of the cursor subsystem may be attained by reference the Cprogramming language code that follows illustrating operation of thecursor subsystem according to one practice of the invention:

#define NumCursorPixs 97 U8 BehindCursor[NumCursorPixs]; const U8CursorImage[NumCursorPixs][3] = { {0, 0,CusorBoader},{1, 0,CusorBoader},{0, 1,CusorBoader},{1, 1,CursorFill}, {2, 1,CusorBoader}, {0,2,CusorBoader},{1, 2,CursorFill}, {2, 2,CursorFill},{3, 2,CusorBoader},{0, 3,CusorBoader},{1, 3,CursorFill}, {2, 3,CursorFill},{3,3,CursorFill}, {4, 3,CusorBoader}, {0, 4,CusorBoader},{1, 4,CursorFill},{2, 4,CursorFill},{3, 4,CursorFill}, {4, 4,CursorFill},{5,4,CusorBoader}, {0, 5,CusorBoader},{1, 5,CursorFill}, {2,5,CursorFill},{3, 5,CursorFill}, {4, 5,CursorFill},{5, 5,CursorFill},{6, 5,CusorBoader}, {0, 6,CusorBoader},{1, 6,CursorFill}, {2,6,CursorFill},{3, 6,CursorFill}, {4, 6,CursorFill},{5, 6,CursorFill},{6, 6,CursorFill},{7, 6,CusorBoader}, {0, 7,CusorBoader},{1,7,CursorFill}, {2, 7,CursorFill},{3, 7,CursorFill}, {4,7,CursorFill},{5, 7,CursorFill}, {6, 7,CursorFill},{7, 7,CursorFill},{8, 7,CusorBoader}, {0, 8,CusorBoader},{1, 8,CursorFill}, {2,8,CursorFill},{3, 8,CursorFill}, {4, 8,CursorFill},{5, 8,CursorFill},{6, 8,CursorFill},{7, 8,CursorFill}, {8, 8,CursorFill},{9,8,CusorBoader}, {0, 9,CusorBoader},{1, 9,CursorFill}, {2,9,CursorFill},{3, 9,CursorFill}, {4, 9,CursorFill},{5, 9,CursorFill},{6, 9,CusorBoader},{7, 9,CusorBoader}, {8, 9,CusorBoader},{9,9,CusorBoader}, {10, 9,CusorBoader},{0,10,CusorBoader},{1,10,CursorFill},{2,10,CursorFill},{3,10,CusorBoader},{4,10,CursorFill},{5,10,CursorFill}, {6,10,CusorBoader},{0,11,CusorBoader},{1,11,CursorFill},{2,11,CusorBoader},{4,11,CusorBoader},{5,11,CursorFill},{6,11,CursorFill}, {7,11,CusorBoader},{0,12,CusorBoader},{1,12,CusorBoader},{4,12,CusorBoader},{5,12,CursorFill},{6,12,CursorFill},{7,12,CusorBoader},{0,13,CusorBoader},{5,13,CusorBoader},{6,13,CursorFill},{7,13,CursorFill}, {8,13,CusorBoader},{5,14,CusorBoader},{6,14,CursorFill},{7,14,CursorFill},{8,14,CusorBoader},{6,15,CusorBoader},{7,15,CusorBoader}, {8,15,CusorBoader}}; voidEraseCursor(S16 CursorLocX, S16 CursorLocY) {  U32 b, x, y;  U8 i;  b =(*(U32*)0x02200850) & 0xFFFFFFF0;  for (i = 0; i<NumCursorPixs; i++)  {  x = CursorLocX + CursorImage[i][0];   y = ((CursorLocY +CursorImage[i][1]) * 640);      //Restore Background   (*(U8 *)(b + y +x)) = BehindCursor[i];  } } void DrawCursor(void) {  U32 b, x, y, s;  U8i,c, j;     //Move to New Position  CursorLocX += MoveX;  CursorLocY +=MoveY;     //Check the boundry  if(CursorLocX >= 630) CursorLocX = 630; else if(CursorLocX <= 0) CursorLocX = 0;  if(CursorLocY >= 460)CursorLocY = 460;  else if(CursorLocY <= 0) CursorLocY = 0;  b =(*(U32*)0x02200850) & 0xFFFFFFF0;  for (i = 0; i<NumCursorPixs; i++)  {  x = CursorLocX + CursorImage[i][0];   y = ((CursorLocY +CursorImage[i][1]) * 640);     //Cursor moving to new position,    //Save whole background at new position   if(MoveX || MoveY)   {   BehindCursor[i] = (*(U8 *)(b + y + x));       //Show Cursor Image atnew location    (*(U8 *)(b + y + x)) = CursorImage[i][2];   }else      //Refresh the Cursor image at the       //current location, onlyif the image       //behind the cursor is changed need to be saved   {   if(CursorImage[i][2] != (*(U8 *)(b + y + x)))    {    BehindCursor[i] = (*(U8 *)(b + y + x));     (*(U8 *)(b + y + x)) =CursorImage[i][2];    }   }  }     //Ready for next move  MoveX = MoveY= 0; } void InitCursor(void) {  U16 i;  if(CursorLocX >= 639 ||CursorLocY >= 479)  {   CursorLocX = 320; CursorLocY = 240;  }  MoveX =MoveY = 0;  for (i = 0; i<NumCursorPixs; i++)   BehindCursor[i] = Red; CursorTimer = 101; } void HandleCursor(void) {  if((MoveX || MoveY) &&!SetToNewTx)  {   if(CursorTimer != 101)     //At the CurrentPosition   EraseCursor(CursorLocX, CursorLocY);   SimulateTouch = 2;  CursorTimer = 0;  }  if(CursorTimer < 100)  {   DrawCursor( );  }elseif(CursorTimer == 100)  {   EraseCursor(CursorLocX, CursorLocY);  SimulateTouch = 2;    CursorTimer = 101;  } }

Touchpad Subsystem

The touchpad subsystem 26 b comprises software that identifies gesturesby the user on the touchpad 18 and, in response, generates notificationsindicative of the type, location (e.g., start and/or end position on thetouchpad 18), magnitude and/or direction of the gestures. Those gesturesinclude at least a contacting touch of length (e.g., a linear orcurvilinear swipe) and may, optionally, include a tap or point touch(i.e., a contacting touch of substantially no length). The notificationscan be used by application 28 a and/or the main image subsystem 24 a toalter display of an application window—e.g., to highlight a newlyactivated hot spot and/or to display a value selected by the user viathe gesture. The notifications can also be used by the application 28 aas indicative of substantive user input, e.g., numeric, alpha or othervalue selections, based on the type of activated hot spot, theuser-selectable values associated with that hot spot, the gesture type,location, magnitude and/or direction. The cursor subsystem 26 a can alsouse such notifications from the touchpad subsystem and/or subsequentresultant notifications front the application 28 a to generate acursor-representative signal for repositioning a cursor on the monitor16, e.g., within a newly activated hot spot.

FIGS. 5a-5f, 6a-6e, 7a-7e, and 8a-8d depict, by way of non-limitingexample, user gestures on touchpad 18 and their effect on a userinterface generated by application 28 a for display on monitor 16. Eachof those figures is in two parts: an upper part depicting the userinterface generated by application 28 a and driven to the monitor viamain image subsystem 24 a and graphics logic 22 f e.g., as describedabove; and, a lower part, depicting user gestures (e.g., swipes andtouches) on touchpad 18. Application windows depicted in these figuresmay include, in addition to the illustrated user interfaces, other textand graphics—not shown, here, for sake of simplicity—generated byapplication 28 a relating to medical treatment apparatus 12, treatmentof patient 14. and/or other aspects of patient care, by way ofnon-limiting example. Like elements of these figures are not labelledwith reference numbers to avoid clutter and for sake of simplicity.

Referring to FIG. 5a , by way of example, there is shown an applicationwindow 56 of the type generated by application 28 a and displayed onmonitor 16 with a graphical user interface that includes user selectableand/or manipulable hot spots 60-64, here, representing a menu (60) andtwo buttons (62, 64). None of those elements are highlighted oractivated, as indicated by an absence of boldface type and/or thicklines. A cursor 58 of the type generated by cursor subsystem is alsoshown, here, in its default position in the center of window 56.

Referring to FIG. 5b , there is shown a user swipe 66 on touchpad 18.Here, the swipe is in an upward let) direction. In the illustratedsystem, such a swipe results in activation one of the hotspots as afunction of one or more factors, including: gesture type, location ofthe gesture on the touchpad, magnitude and/or direction of the gesture,current position of cursor 58, and/or location of the currentlyactivated hotspot, if any. Various embodiments may use fewer or morefactors and or may weight these factors differently from one another. Asevident in the discussion that follows, for swipe-type gestures, theillustrated embodiment principally weights (i) direction of the gesture,and (ii) current position of cursor 58 and/or location of the currentlyactivated hotspot. Those skilled in the art will appreciate, in view ofthe teachings hereof, how these and other embodiments may makeadditional or alternate use of the other factors (aforementioned orotherwise).

Turning back to FIG. 5b , the swipe results in activation of menu 60,since that hotspot is left of the current cursor position. Activation ofthat hotspot may be indicated in any number of ways in the userinterface, when it is regenerated by application 28 a followingnotification of the swipe by touchpad subsystem 26 b. For example, theapplication 28 a may show that hotspot 60 with a bold line about itsperimeter, as in the drawing. The application 28 a may, instead or inaddition, indicate such activation by regenerating the user interfacewith the hotspot 60 depicted with varied color, intensity and so forth.

In the illustrated system, the swipe also results in repositioning ofcursor 58 to a location nearer, e.g., on the perimeter of or within thehotspot 60, as shown. This is effected by action of the cursor subsystem26 a in response to notification of the swipe from the touchpadsubsystem 26 b and/or the application 28 a. Similar cursor repositioningis generally shown in applicable ones of FIGS. 5c-8d , with littlecomment in the text that follows.

Referring to FIG. 5c , a user tap on touchpad 18 and/or one if itsattendant buttons (here, left touchpad button 68) confirms selection ofthe hotspot 60. Here, that tap is conveyed by a notification from thetouchpad subsystem 26 b to the application 28 a, which can againregenerate the user interface with further variation—e.g., furthersignifying to the user that the hotspot has been activated. Here, thatfurther variation is the boldface display of the menu title (“MainMenu”), though, in other embodiments, other indications may be usedinstead or in addition. Though the tap shown in FIG. 5c is made onattendant button 68 (as is the case with similar taps shown inapplicable ones of FIGS. 5d-8d ), it will be appreciated that those tapscan be made directly on touchpad 18, instead or in addition.

Referring to FIG. 5d , there is shown a further user swipe 66 ontouchpad 18, here, in a downward direction. With hotspot 60 alreadyactivated, this swipe results in selection of the nearestuser-selectable value of the hotspot from (a) the current position ofcursor 58, and/or (b) a previous selected value (if any) in thedirection indicated by the swipe. Here, the swipe results in selectionof the topmost menu option (“Select Patient”), since that is the nearestuser-selectable value in the downward direction from the cursor and fromthe title that was activated in connection with the actions shown inFIG. 5c . As above, selection of the value may be indicated in anynumber of ways in the user interface, when it is regenerated byapplication 28 a following notification of the swipe by touchpadsubsystem 26 b. For example, the application 28 a may show thatselection with boldface type, varied color, intensity and so forth.

Referring to FIG. 5e , a user tap on touchpad 18 and/or one if itsattendant buttons (here, again, left touchpad button 68) confirms theselection. As above, that tap can be conveyed by a notification from thetouchpad subsystem 26 b to the application 28 a, which can againregenerate the user interface with further variation of the selectedvalue. Alternatively (or in addition), as shown in FIG. 5f ,confirmation of the selection can be signified by generation of afurther user interface including further hotspots corresponding to theuser's selection. In the drawing, that interface comprises threeuser-selectable hotspots 74, each with text and graphics identifying apatient of interest (e.g., a patient currently being treated and/or forwhom medical treatment information is to be entered, recorded, output,or so forth). In practice, additional hotspots, such as “exit” and“back” buttons, may be included, as well.

In a manner paralleling the actions described in connection with FIGS.5a-5f , above, FIGS. 6a-6b depict selection of the hotspot correspondingto “Patient 2” via a two downward swipes on touchpad 18 (FIG. 6a ) andconfirmation of the hotspot via a tap (FIG. 6b ). As an alternative tothe use of two downward swipes in connection with the actions depictedin FIG. 6a , the application 28 a of some embodiments can respond to aswipe of larger magnitude (as detected by touchpad subsystem 26 b) toselect a farther hotspot (i.e., one other than that nearest the cursoror currently activated hotspot in the direction of the swipe).

Continuing the example in the same vein as discussed above, FIG. 6cdepicts a still further user interface including hotspot 80 generated byapplication 28 a following confirmation of selection of the “Patient 2”hotspot in FIG. 6b . The interface includes, inter alia, three hotspots78—here, user-selectable buttons for calling up the patient's pulse,blood pressure and/or potassium level history and/or entering thosevalues. As depicted in FIGS. 6d-6f , further swipes on the touchpad 18can effect activation of those respective buttons: an upward right swipefor activation of the pulse button (FIG. 6d ); a subsequent downwardswipe for activation of the blood pressure button (FIG. 6e ); and afurther downward swipe for activation of the potassium levels button (6f). As illustrated here and applicable throughout, in some embodiments,those swipes need not necessarily be confirmed, e.g., via a separate tapon the touchpad (or an associated touchpad button). More particularly,as shown in FIGS. 6d-6f , with activation of each of the respectivehotspots/buttons 78, the application 28 a displays additionalcorresponding hotspots 82-88, as shown.

The hotspot activation depicted in FIG. 6d , is shown with furtherparticularity in FIGS. 7a-7e , again, in a manner paralleling theactions described above. Thus, for example, FIGS. 7a-7c depictsselection of the pulse button from among hotspots 78. This mirrors theactions shown in FIG. 6d and described immediately above, albeit, here aseparate tap on the touchpad or an associated touchpad button 68 isutilized to confirm the swipe (FIG. 7b ) prior to display of theinterface including the corresponding hotspot 82 (FIG. 7c ). FIGS. 7d-7eillustrate use of touchpad swipes and taps in connection with menuhotspot 82 to select a value 88 (here, a blood pressure value of “62”)for input to application 28 a. As above, that application can regeneratethe interface, including new values for hotspot 82, with each useraction. For example, following selection of the value 88, theapplication 28 generates confirmatory text identifying the selectedvalue.

An alternate use of a hotspot for value selection and input is shown inFIGS. 8a-8d . This parallels the activity shown in FIGS. 7d-7e , albeitwith a hotspot 82′ that displays a user-adjustable value forpulse—absent, for example, a menu or “dial-wheel” metaphor. Moreparticularly, following selection of the pulse button hotspot 78 asshown in FIG. 6d and discussed in connection therewith, application 28 aregenerates the interface with hotspot 82′ activated and a default value(here, 65) displayed. See, FIG. 8a . FIG. 8b depicts tentativeadjustment of that value (to 62) via three downward swipes by the useron touchpad 18), and FIG. 8c depicts re-adjustment of that value (to 66)via four upward swipes. In FIG. 8d , the user confirms that value via atap. As above, application 28 a regenerates the interface, including newvalues for hotspot 82′, with each user action. And, followingconfirmation (FIG. 8d ), the application 28 a generates confirmatorytext identifying the selected value.

FIG. 9 is a data-flow diagram depicting, by way of non-limiting example,a manner in which the touchpad subsystem 26 b identities gestures andnotifies application 28 a and/or other element of the illustratedsystem. The data-flow of FIG. 9 parallels that of FIG. 3, discussedabove, as adapted in view of the immediately preceding discussion ofFIGS. 5a-7e . Thus, for example, as shown in that drawing, a user ofdata entry station 10 effects activation of hotspots and selection ofvalues within activated hotspots (collectively, “selection of hotspots”)by touching and/or moving his/her finger on the touchpad 18 (or otherdevice) in the conventional manner known in the art, as adapted inaccord with the teachings hereof. The touchpad 18 responds by generatingsignals indicative of that touch/movement for input to serial port 22 d,which in turn generates an interrupt for application to CPU 22 a alongwith the touch/movement information—all in the conventional manner knownin the art, as adapted in accord with the teachings hereof. Operatingsystem 24 notifies touchpad subsystem 26 b of the touchpad activity andmakes that touch/movement information available to it. As above, thiscan be effected, by way of non-limiting example, by interrupthandling-code that comprises the and/or invokes the cursor subsystem 26a and that stores the touch/movement information to memory for use byit.

Upon notification of the touchpad activity, touchpad subsystem 26 bdetermines what type of gesture it represents, e.g., touch, swipe, andso forth. It also retrieves from information supplied by the operatingsystem 24 the location of the gesture, as well as its direction andmagnitude. The touchpad subsystem supplies that information toapplication 28 a, which determines, based on, the current position ofthe cursor and/or location of a currently activated hotspot, as well ason the gesture type, location, magnitude and/or direction what hotspotto activate or, in the event a hotspot is already activated, whatuser-selectable value associated with that hotspot to select—all in themanner as discussed, by way of non-limiting example, above. Theapplication 28 a regenerates an application window, including, text andgraphics highlighting a newly activated hotspot or user-selectable valueand passes it to the main image subsystem for generation ofcorresponding screen-representative signals, as discussed above.

The touchpad subsystem also supplies the touchpad touch/movementinformation, or a subset thereof, to cursor subsystem 26 a, whichassumes or calculates a tentative new cursor display position asdiscussed in connection with FIG. 3. The tentative position, however,may be overridden by values supplied by application 28 a, based on itsdetermination of the location of a newly activated hotspot and/orselection of a value associated therewith. The cursor subsystem 26 asubsequently updates VRAM 22 e as discussed above to effectrepositioning of the cursor to that new location.

Described herein are systems, apparatus and methods meeting the objectsset forth above, among others. It will be appreciated that theillustrated embodiments are merely examples of the invention and thatother embodiments employing modifications of those illustrated anddescribed here fall within the scope of the invention. Thus, graphicsand/or text defining the user interface and attributed in the text aboveby the application 28 a can be generated by the operating system 24and/or middleware/software 26, instead or in addition. Likewise,response by the application 28 a to notifications from the touchpadsubsystem can be handled by functionality associated with the operatingsystem 24 and/or the middleware/software 26, instead or in addition.

In view of the foregoing, what we claim is:
 1. Medical apparatus with auser interface comprising: a processor that executes an application thatgenerates a user interface for display on a monitor, the user interfaceincluding text and/or graphics comprising buttons, widgets or otheritems selectable and/or manipulable by a user (collectively,“hotspots”), a video memory that is in communications coupling with theapplication and that stores information (“screen-representativeinformation”) representing the user interface generated by theapplication, a touchpad subsystem that is in communications couplingwith the application and with a touchpad and that generates anotification in response to a gesture thereon, where the touchpad isseparate from the monitor and that gesture is a swipe, and where thenotification includes a magnitude and a direction of the swipe on thetouchpad, the application responding to the notification by activating anext said hotspot and displaying on the user interface an effect of suchactivation on the user interface, wherein the application activates saidnext hotspot as a function of the magnitude and the direction of theswipe on the touchpad with respect to a location of a currentlyactivated hotspot.
 2. Medical apparatus according to claim 1, whereinthe touchpad subsystem generates the notification in response to a swipethat comprises any of a linear and curvilinear swipe.
 3. Medicalapparatus according to claim 1, wherein the touchpad subsystem generatesfurther notifications in response to a tap on the touchpad.
 4. Medicalapparatus according to claim 1, wherein the application generates theuser interface to highlight an activated hotspot.
 5. Medical apparatuswith a user interface comprising: a processor that executes anapplication that generates a user interface for display on a monitor,the user interface including text and/or graphics comprising buttons,widgets or other items selectable and/or manipulable by a user(collectively, “hotspots”), a video memory that is in communicationscoupling with the application and that stores information(“screen-representative information”) representing the user interfacegenerated by the application, a cursor subsystem that is coupled to thevideo memory and that modifies at least a portion of thescreen-representative information therein with information(“cursor-representative information”) representing a cursor, graphicslogic that is coupled to the video memory and to the monitor and thatdrives the screen-representative information and thecursor-representative information in the video memory to the monitor fordisplay thereby of graphics and/or text generated by the applicationoverlaid with a graphic of the cursor, a touchpad subsystem that is incommunications coupling with the application and with a touchpad andthat generates a notification in response to a gesture thereon, wherethe touchpad is separate from the monitor and that gesture is a swipe,and where the notification includes a magnitude and a direction of theswipe on the touchpad, the application responding to the notification byactivating a next said hotspot and displaying on the user interface aneffect of such activation on the user interface, wherein the applicationactivates said next hotspot as a function of the magnitude and thedirection of the swipe on the touchpad with respect to a currentposition of the cursor.
 6. Medical apparatus according to claim 5,wherein the cursor subsystem is responsive to user action on thetouchpad for determining a position of the cursor.
 7. Medical apparatusaccording to claim 5, comprising a main image subsystem that is incommunications coupling with the application and with the video memoryand that writes to the video memory the screen-representativeinformation representing graphics and/or text generated by theapplication.
 8. Medical apparatus according to claim 7, wherein, inconnection with writing the screen-representative information to thevideo memory, the main image subsystem overwrites thecursor-representative information previously written by the cursorsubsystem to the video memory.
 9. Medical apparatus according to claim8, wherein the cursor subsystem responds to a change in thecursor-representative information previously written by it to the videomemory by re-writing the cursor-representative information to the videomemory.